The present invention relates to a device that, when a paper roll being fed into a printing machine reaches its end (is expiring), it automatically prepares the leading web end of a new roll for automatic web-to-web pasting by means of an adhesive.
As shown in FIG. 10, a printing system for newspapers or the like includes a printing machine C which is generally fed with a paper web from one of a plurality of paper rolls B rotatively held on a reel stand A. When a paper roll B1 being fed into the printing machine C is expiring, a new paper roll B2 positioned nearest to it, is started rotating by a drive device D and made to rotate at a rate peripherally equal to the rate at which the expiring paper B1 is being fed. A pusher E is then made to press the trailing end of the expiring web from the paper roll B1 against the leading end of the new paper roll B2 so as to paste the two webs to each other by means of adhesive.
Connection of the new paper roll B2 to the expiring roll B1 requires that the leading web end of the new roll be prepared beforehand for this adhesive-based pasting. Conventionally, it has been the practice to prepare new paper rolls for pasting entirely by manual procedure substantially in the manner described below, to make a leading web end assume the form shown in FIG. 11.
(1) In order to remove from the paper roll any loose portion or damaged area that may have been caused thereto in transit, the paper roll is stripped of peripheral layers (three to five layers from the peripheral surface) with a spatula or the like;
(2) the leading web end is cut with scissors or the like into a substantially triangular form to adapt it for the pasting;
(3) the tip of the web edge thus formed is fastened to the peripheral surface of the paper roll B by means of an adhesive web edge fastening strip F.
(4) strips of adhesive tape G for adhesion in pasting are adhesively attached to the V-shaped leading web end.
The manual process to carry out all of these steps has been very inefficient and costly as well. Another problem has been an excessive loss of paper incidental to the manual process because the manual removal of the peripheral layer is liable to damage inner layers that otherwise are good for use.